It’s interesting that you have been told that leech telltales are worthless.

When I sailed the 2002 Performance Nationals on Traverse Bay Michigan, a couple of French F-18 rock stars gave a seminar and they said they only use leech tell tales to trim their main. The objective is to keep the tales just starting to flick to the lee side of the sail. To me this logic made sense, this should be the first place the sail begins to stall. If the tales are constantly flowing back you are under sheeted, if they constantly on the lee side of the sail you are over sheeted. I also have a set of tell tales on the luff of the sail. I focus on the outside and the leech tales and pretty much ignore the inside luff tell tail.

If I’m completely out to lunch on this one please correct me and explain why. Please try to keep the jargon straight forward I am not an aerodynamics engineer.

Thanks in advance,
David Ingram